Friday, November 1, 2024

Recap: Alyssa Ney's Metaphysics: Chapter 8 - Time (Part 1)

Approaching this chapter on time, I am slightly familiar with the topic given my listening of various interviews and podcasts with Ryan Mullins, who has a book called The End of the Timeless God (2016). Just two weeks ago, Mullins released his new book: From Divine Timemaker to Divine Watchmaker: An Exploration of God’s Temporality (2024).

His podcast can be found here: https://www.rtmullins.com/podcast/

Mullins gives an overview of time in this podcast: https://www.rtmullins.com/podcast/episode/1e9ec548/ep-85-what-is-time, and in this interview (The Analytic Christian): https://www.youtube.com/watch?v=7xeRN9-9PTE, and this interview (Adherent Apologetics): https://www.youtube.com/watch?v=o1het_5Y1zU.

I’m also familiar with William Lane Craig, who has made a great effort in researching the relationship between God and time. Ney even cites Craig for further reading (Craig’s 2001 book Time and the Metaphysics of Relativity and the 2001 book The Tensed Theory of Time: A Critical Examination). Craig defends presentism, a view I define below. I’ve absorbed some knowledge of the topic from listening to Craig through his Reasonable Faith podcast and from reading his QnAs and articles on his website reasonablefaith.org.

There are five terms we must immediately define when it comes to philosophy of time: 
Time, Presentism, A-Theory, Eternalism, and B-Theory. Let’s start with time.

Like ‘existence’ and ‘knowledge’, time is tricky to define despite its familiarity. As Mullins relates, St. Augustine once said that he knows what time is until you ask him.

Before we get into a definition of time, let’s make some observations about time:

  • Time passes.
  • There is a past, present, and future.
  • When time passes, the future becomes the present and the present becomes the past (and the past becomes the distant past).
  • There is an arrow of time: everything is moving forward in some temporal sense. You never get younger, only older. We feel ourselves being pushed forward, away from past events and toward future events.
  • There are timelines or “chunks of time” featuring a succession of moments (or events) where any moment (or event) is earlier than, later than, or simultaneous with all other moments (or events) in the timeline. We might say there is the timeline, the history of the universe, which is estimated to be 13.8 billion years old.
  • We measure the passage of time using clocks and calendars, and we record the passage of time through books, letters, emails, websites, receipts, journals, videos, photos, our memory, etc.

How do we make sense of these facts of time? Mullins shares two views: the relational theory and the absolute theory.

Relational theory: This view says time cannot exist without change, and that time is reduced to a relationship between events. Events are the more fundamental thing that give rise to time. But this leads to a problem: How do we describe this relationship between events? If we say one event is before or after or simultaneous with another event, then we have made no progress, as it is exactly these temporal ideas (before, after, simultaneity) that we are trying to understand in non-temporal terms. If we are reducing time to something non-temporal, like events, then we should be able to translate all temporal terms into non-temporal language.

I’m not sure this circularity objection works. Maybe temporal relations are simple and cannot be explained in non-temporal terms, in which case it's fine to say that time is a category of simple relations between events. In other words, it's a brute fact that some things are before other things. There is no explanation as to what this before consists of. Or, we might say that explanation bottoms out in necessity when it comes to temporal relations. In other words, the necessary foundation of the universe necessarily causes or explains all of nature, including space and time. If we think of properties as being those things that allow us to describe things, then we may find ourselves committed to those properties that are needed to explain things. Certainly, we need temporal notions to describe things, so we need temporal properties. But what these temporal properties are, maybe that's an unanswerable question.

But are events even non-temporal in the first place? Per Mullins, E. J. Lowe defines an event as a substance having a property at a time. Per Mullins, Ulrich Meyer points out that standard definitions of events, like E. J. Lowe’s, presuppose temporal notions. But we can’t reduce time to events if events are defined in terms of time!

Craig, who defends the relational theory of time, responds to this objection briefly here at the 33 minute mark: https://www.rtmullins.com/podcast/episode/2d74fe0b/ep-84-william-lane-craig-on-god-time-and-creation. Craig defines events as simply “that which happens,” removing any temporal notion within events.

Absolute theory: This view says time is (1) an eternal, natured entity (2) that makes change possible, (3) is the ontological source of moments, and is (4) that which orders a set of successive moments into a coherent timeline. A moment of time is a when an event happens. In Mullins’ interview with Kristie Miller, a moment of time is said to be a snapshot of the universe where everything is frozen and unchanging. (I’ve also heard the idea that a moment is the smallest unit of time if time is discrete, and if time is continuous then there are an infinite number of moments within any timeline.)

Metric time: Mullins mentions that time itself needn’t have a metric (a standard of measurement or ability to be measured, I’m guessing ). For time to have a metric, we need uniform laws of nature to provide the basis for consistent periodic changes. I’ve heard Craig also make the distinction between metric and non-metric time. I’m guessing this means something like: in metric time we can count seconds, minutes, days, years, and so on. In non-metric time we can only say that some things happen before or after other things. See Craig here: https://www.biola.edu/blogs/good-book-blog/2017/how-to-answer-objections-a-case-in-point.

A-Theory: When we say “time passes”, we are saying something strictly true. Time is dynamic; the flow of time is real; there is an objective difference between past, present, and future. Tensed facts cannot be reduced to tenseless facts.

B-Theory: When we say “time passes”, we are saying something strictly false, or true only in a subjective sense. Time is static; there is no real flow of time; there is no objective difference between past, present, and future. Tensed facts can be reduced to tenseless facts.

To see the difference between the two, consider: “The year 2000 was 24 years ago.” On the A-Theory of time, this is true in an absolute, objective sense. But on the B-Theory of time, this sentence doesn’t make sense, and instead you would have to say “The year 2000 is 24 years prior to the year 2024.” On the B-Theory, any tensed statement can be relativized, and this is what it means to say tensed facts can be reduced, or translated, to tenseless facts.

Presentism: The view that all objects and events in the past have ceased to exist, and all objects and events in the future have yet to exist. Only present objects and events exist.

Eternalism: The view that all objects and events of the past, present, and future exist simultaneously.

I had thought that ‘A-Theory’ and ‘presentism’ meant the same thing – same with ‘B-Theory’ and ‘eternalism’ – but these things come apart. We have what Ney refers to as four metaphysics of time. These seem to be “full views” of time that combine both a view on the objectivity / subjectivity of the passage of time (A-Theory vs B-Theory) with the existence of past, present, and future objects / events (presentism vs eternalism). These four views are: Presentism (Presentism + A-Theory), Growing block theory (modified presentism + A-Theory), moving spotlight theory (eternalism + A-Theory), and block universe theory (eternalism + B-Theory).

It’s confusing to have the word ‘presentism’ denote both a theory of the ontology of past, present, and future objects / events and a metaphysics of time. That, plus how readily A-Theory and presentism are paired together, it’s no surprise that someone would confuse the two.

Another source of confusion, for me at least, is that any one of these, plus the absolute / relational theories, can be called a ‘theory of time.’

Attempting (and not necessarily succeeding) to remove confusion, I will define things in the following way:

Layer 1 (Theories of time itself) - What is time? Is it a substance, a relation, a property, a law of nature, a spatiotemporal, four-dimensional substructure of the universe, or purely a faculty within the mind like Kant said? Is time a primitive notion? Is time something in itself or just something that emerges from change? Does change give rise to time (i.e., is time reducible to change or events), or does time enable change (i.e., is time irreducible)? Is time irreducible (Absolute theory) or reducible (relational theory)? 

Layer 2 (Theories of the passage of time) - Is the passage of time objective (A-Theory), or subjective (B-Theory)?

Layer 3 (Theories of temporal ontology) - Do only present objects and events exist (Presentism)? Or does the universe grow in its ontology where past and present, but not future, objects / events exist (growing block theory)? Or can all tensed facts be translated into tenseless facts, there is no privileged, objective present moment, time is relative to observers, and so past, present, and future objects / events are equally real (eternalism)?

Layer 4 (Metaphysics of time) - Combining layers 2 and 3
1) Presentism + A-Theory (Because presentism entails A-Theory, we just call this Presentism).
2) Growing block + A-Theory (likewise, growing block entails A-Theory, so we just call this Growing block theory).
3) Eternalism + A-Theory = Moving spotlight theory.
4) Eternalism + B-Theory = Block universe theory (eternalism entails B-Theory, so we could just call this eternalism like we call metaphysical presentism 'presentism'… but anyway).

This terminology stuff is a bit frustrating and ugly, and I wish there were a neat way to carve things up. This will do for now until I find a better approach.

In the next post, I will cover more of Ney’s chapter in time where we get into arguments for and against some of these views.

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